The present invention relates generally to dentistry and specifically to a method, apparatus and monitoring device for the treatment of various problems related to improper use of jaw musculature and/or to monitor a patient""s compliance with his or her treatment regimen.
There are numerous dental problems that arise from improper use of jaw musculature. One of these is clenching, a condition in which a patient constantly or excessively presses his or her teeth against each other. Clenching can cause excessive wear of the teeth, headaches, and fatigue and soreness of the jaw muscles.
There are at least three schools of thought on the treatment of clenching. One traditional treatment involves placing a protective layer of acrylic material (called a splint) over the involved teeth. This acrylic layer serves to protect the teeth from direct contact, thus reducing wear, and to spread the load caused by clenching so that it is shared more equally among the neighboring teeth. This reduces wear of the teeth, but the acrylic protective layer does not address the problem of clenching, which frequently continues indefinitely. This forces the patient to wear the splint indefinitely. In some cases the urge to clench is worsened.
A second traditional treatment for clenching is occlusal adjustment. This treatment involves selective grinding of teeth so that the load on the teeth caused by clenching is carried evenly by several teeth rather than being concentrated on one or two. This technique is successful with some but not all types of clenching.
A third school of thought is that there is nothing that can be done about clenching. This approach may have heretofore had the advantage of candor, but it left patients with unnecessary discomfort. Muscle relaxants are often prescribed in these instances. This group of drugs may adversely effect performance, and therefore can in some instances only be used when the patient is at home.
A second class of dental problems relates to what are termed problems in the vertical frame of reference. Examples of these problems are: (1) Dental open bite which is characterized by contact between the posterior teeth without contact between the front teeth when the jaw is closed; (2) skeletal open bite which is characterized by a sloping mandibular plane and a long face; and (3) skeletal deep bite which is characterized by short faces and mandibular planes that are nearly horizontal or parallel with the floor. Skeletal deep bite patients also have dental deep bite which is characterized by excessive overlap of the front teeth. Treatments for problems of this type are discussed below.
One method of treating a dental open bite is to mount ceramic magnets on the rearmost molars with like poles facing each other so that the molars are slowly forced more deeply into the bone which supports them. A disadvantage to this method is that the magnets and their acrylic housing force the jaw open 5-6 millimeters in the rear and perhaps twice that at the front. This forces the patient to walk around with his or her mouth open, which is embarrassing and uncomfortable. Patients also have difficulty keeping their jaws in such a position that the repelling magnets are directly opposing one another. Thus, there is a tendency for the lower jaw to slide from side to side and not to stay centered. As a result, these patients are frequently asked to wear a chin strap and headgear apparatus to center the lower jaw. This method of treating open bites is prone to the problem of lack of patient cooperation.
Another problem associated with dental open bites is called tongue thrusting. A patient with this problem habitually presses his or her tongue forward against his or her front teeth. This problem can be addressed by placing a cage directly behind the upper or lower front teeth. This appliance restrains the tongue from coming forward where it has forced the front teeth apart. The patient is instructed to keep the tongue behind the cage without touching it and to move the tongue backward, away from the cage whenever it touches the cage. The problem with this appliance is that patients forget to remind themselves to move their tongues backward, and they rest their tongues against the cage. When the appliance comes off, the tongue frequently comes forward to rest against the front teeth again. Relapses frequently occur.
When dental open bites are present in patients in their teens, or later as an adult, the treatments for dental open bite are orthodontic treatment in combination with extractions of permanent teeth, or orthodontic treatment in combination with surgery, which usually includes extraction of permanent teeth.
Skeletal open bites are traditionally treated by orthodontists through the use of orthodontics, possibly including the extraction of teeth, and using orthopedic force in the form of headgear which imposes an intrusive force to the maxilla and maxillary teeth. Extractions help to solve the problem in a minor way and require the removal of four perfectly good teeth. The successful use of headgear is dependent upon the cooperation of the patient. The headgear includes a brace that circumscribes the head and neck, and it is cumbersome and uncomfortable. Experience has shown that cooperation in wearing the headgear is often less than complete. The use of extractions and headgear treat only the symptoms of skeletal open bites. The underlying cause of the problem which is the lack of sustained contact between the teeth is not addressed by this treatment.
Dental and skeletal deep bite are treated by orthodontists through the use of an orthodontic regimen which often includes propping the front teeth open with an acrylic bite plane. This leaves the posterior teeth apart and allows them to erupt into contact with each other. In the short run this treatment appears to be stable, but after about a year the deep bite may begin to return because the underlying cause of the problem (chronic clenching of teeth) was never addressed.
Another class of dental problems relates to what is termed problems in the horizontal frame of reference. Mandibular retrognathia is one such problem. It is characterized by the lower jaw being positioned too far behind the upper jaw in the horizontal frame of reference. This condition is conventionally treated with bulky acrylic appliances which hold the lower jaw forward and restrain the lower jaw from moving backward. These appliances have been shown to create undesirable side effects related to this restraint such as proclination of the lower anterior teeth. Other treatments have been: Orthodontics that usually includes extraction of teeth, or orthodontics that utilize orthopedic forces to push the upper jaw backward to meet the lower jaw. If the problem of mandibular retrognathia has not been treated by 12 to 14 years of age, it is often necessary to treat the problem with orthodontics in combination with surgery that is designed to bring the lower jaw forward.
Other classes of dental problems arise when patients fail to wear their dental splint, retainer or other corrective dental hardware. Patients, especially younger patients, routinely hinder their treatment program by failing to wear the prescribed dental hardware. When asked, most patients will not confess to the failure to wear their prescribed dental hardware. Accordingly, there is a need for an appliance which can monitor whether a patient is in compliance with his or her prescribed hardware regimen.
The present invention provides a new approach to treating and monitoring the dental problems discussed above. The present invention can remind the patient of unconscious, undesirable behavior every time it occurs and can help the patient to learn new habits. In addition, the present invention permits a patient""s treating dentist or orthodontist to monitor the patient""s progress through each patient""s prescribed treatment regimen. This is accomplished by the use of electronic circuitry attached to, e.g., the upper teeth which senses the proximity of the lower teeth and signals the patient when the jaw is in an undesirable position. The circuitry also contains a memory and readout apparatus. The memory and readout apparatus may permit a treating dentist or orthodontist to monitor the amount of time and number of times bite forces exceed a predetermined threshold. In addition, the memory and readout apparatus may permit the monitoring of jaw positions by recording the amount of time the teeth are more than a predetermined distance apart, the amount of time the teeth are together and/or the number of times biting occurs.
For patients who clench, the circuitry may sense a closed jaw, and when the jaw has been held closed too long, e.g., 3 or 5 seconds, a signal (be it audible or otherwise) is generated alerting the patient to relax his or her jaw muscles by opening the jaw. Conversely, with open bite patients the circuitry may be arranged to signal and monitor the patient when the jaw has been open too long. Additionally or alternatively the present invention may signal and monitor the patient when his or her tongue is being pressed against the back sides of the front teeth. By providing a signal to the patient at the appropriate time, the patient can modify his or her behavior so that the cause of the patient""s problem can be treated: Clenchers learn to relax their jaw muscles; open bite patients strengthen their jaw muscles; and tongue thrusters learn not to press against their teeth. By monitoring the above conditions the present invention permits a dentist or orthodontist to have an objective means of monitoring and diagnosing the progress (or lack thereof) a patient is making progress in their treatment regimen.
This invention may also be adapted to create habits that are lacking by reminding the patient when the desired habit or function is not being practiced. Examples of this application are in the treatment of skeletal open bite or mandibular retrognathia. In skeletal open bite patients there is thought to exist a lack of sustained contact between upper and lower jaws. This results in the tendency for the face to grow downward instead of forward. The result is these patients have extremely long faces. By using the present invention to sense the lack of contact between teeth, the patients can be trained to keep their teeth in contact during certain periods during the day. This stops or reverses the downward growth and at the same time trains the muscles to keep the lower jaw in more frequent contact with the upper jaw. Additionally, the above device can be configured to permit it use in training mandibular retrognathia patients to hold their jaws forward in the correct lower jaw position.
The present invention includes an electronic circuit which may comprise a reed switch, time delay, oscillator, signal generator (e.g., a sound production or light emitting device), memory component, readout device and power supply all encapsulated in suitable plastic material (e.g., an acrylic or a watertight synthetic resin) and mounted to a molar, usually a maxillary molar. To treat clenching or open bite problems the opposing molar carries a small magnet to actuate the reed switch. The device is removably mounted to a band surrounding the tooth so that it may readily be removed for repair or when it is not desirable to have it operating. With regard to the readout device, it can be integrated into the device as mounted in the patient""s mouth thereby permitting the doctor to directly monitor the patient""s progress during an office visits. In another embodiment, the device can be set up to include an integrated readout device so as to permit the patient to monitor his or her own progress between office visits.
In one embodiment, the device can have connectors which permit a treating dentist or orthodontist to attach a readout device to display the information contained within the device""s memory. In another embodiment, the device can include circuitry which can produce a series of audible beeps which are coded to represent the data contained in the device""s memory. These beeps can be recorded by a device outside the patient""s mouth and then translated to yield the data contained within the device""s memory.
In another embodiment, the device can contain circuitry which generates a signal comprising a slight vibration (similar in nature to that of a pager). Such a vibrational mode is advantageous in that it is quite and does not interrupt other individuals in the immediate vicinity of the patient. In another embodiment, the device can contain a means to permit switching between an audible mode and a vibrational mode.
To treat tongue thrusting, a cage is mounted just behind the upper front teeth. The cage is movable and spring biased rearwardly to a position slightly spaced from the upper front teeth. When the tongue is pressed against the cage, the cage moves forward. A magnet is mounted to the cage, and when the cage moves, the magnet actuates the circuitry to alert the patient. The tongue thrusting treating device is mounted by means of a pair of polymeric splints which surround the three or four rearmost maxillary teeth on each side and in one of which the circuitry is embedded. The splints are connected by thick wires or bars which are contoured to follow the roof of the mouth. Because tongue thrusting is often accompanied by an open bite, additional circuitry which can be arranged to detect an open bite may also be embedded in one of the polymeric splints. The monitoring function of the present invention enables a treating dentist or orthodontist to monitor the number of times and/or amount of time the tongue is thrust forward.
The invention may also be adapted to be incorporated into a retainer or other corrective dental device. In such a situation the monitoring function of the present invention permits a treating dentist or orthodontist to monitor the amount of time the corrective hardware has spent at or above a certain temperature. This enables the treating dentist or orthodontist to ascertain whether such corrective dental appliances have been worn as prescribed.